I am successfully running the example from the metro-source-2.2.1-1\samples\ws-security\src\mcs
Then I include the DisableInclusivePrefixList Assertion in the PingService.wsdl and wsit-client.xml
The example still runs successfully, and the PrefixList disappear from the Signature as expected.

BUT : then I modify the Department data type in the Service_schema.xsd to include an anyType element .
like this :